Study of Regiochemical Trends During the Synthesis of Furan and 5‐(p‐chlorophenyl)Furan Containing Novel Spiropyrrolidine Library Through 1,3‐dipolar Cycloaddition Reactions

Abstract

A new class of functionalized furan and 5-(p-chlorophenyl)furan containing spiropyrrolidines has been synthesized in moderate to excellent yields by the one-pot, three-component 1,3-dipolar cycloaddition reaction of in situ generated azomethine ylides with various furan/aryl furan-substituted chalcones as dipolarophiles. The effect of electron deficient substituents at the fifth position of the furan ring in the chalcone on the regiochemistry of the cycloaddition formed was studied. The structures of the newly synthesized cycloaddicts were proved by analytical and spectral data.

One‐pot three‐component 1,3‐dipolar cycloaddition of azomethineylides to nitrofuran containing acetylenic ketones and molecular docking studies of the cycloadducts

“…The in‐situ generation of azomethineylides by the reaction of ninhydrin or isatin derivatives with α‐aminoacids is well known in the literature. [ 18–20 ] Besides, the nitrofuran containing acetylenic ketones can be easily prepared by the Claisen‐Schmidt condensation of 5‐nitrofuran‐2‐carbaldehyde with different acetophenones followed by its bromination and dehydrobromination. [ 22–24 ]…”

“…Previously we have reported the 1,3‐dipolar cycloaddition of azomethineylides generated from ninhydrin and sarcosine with furan containing and 5‐nitrofuran containing chalcones (Scheme 1). [ 18–20 ]…”

“…Earlier reports showed that the furan containing chalcone gives two possible regio‐isomers approximately in equal quantities during the 1,3‐dipolar cycloaddition reaction (Scheme 1a). [ 18 ] However, the introduction of a nitro group into the 5th position of the furan ring turns it to a highly regioselective one (Scheme 1b). [ 19,20 ]…”